This invention relates to wireless microphones of the type used by singers during stage performances.
The conventional wireless microphone is a generally cylindrical device with the microphone or sound pickup unit mounted at one end within a protective wire screen. An audio amplifier and a radio frequency amplifier are mounted within the body along with associated power supply and control devices. An antenna is mounted at the end of the device opposite the microphone unit. Several types of antenna constructions have been utilized in the past, but all provide for some type of antenna projecting from the hand held microphone. In one prior art unit, a metal tube is mounted at the end of the housing, with the tube the same diameter as the housing, typically about 11/4 inches diameter and 3 inches long. In another conventional design, the antenna is in the form of a rod or small tube projecting from the end of the housing, typically about 1/2 inch diameter and 4 inches long. A third presently used design has a wire antenna projecting from the housing in the order of 1/8 inch diameter and 6 inches long.
All of these prior art constructions are considered unsightly and the projecting antenna makes the overall unit relatively large and hence more difficult to utilize.
Accordingly it is an object of the present invention to provide a new and improved wireless microphone design which does not utilize any separate projecting antenna structure. A further object of the invention is to provide such a wireless microphone with the internal structure of the unit itself serving as a dipole radiator.
Other objects, advantages, features and results will more fully appear in the course of the following description.